D-Link DWS-3160-24TC, Справочное руководство

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DWS-3160 Series Gigabit Ethernet Unified Switch Web UI Reference Guide
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The fields that can be configured are described below:
Parameter Description
Old Local Enable
Password
If a password was previously configured for this entry, enter it here in order to change
it to a new password
New Local Enable
Password Enter the new password that you wish to set on the Switch to authenticate users
attempting to access Administrator Level privileges on the Switch. The user may set a
password of up to 15 characters.
Confirm Local Enable
Password Confirm the new password entered above. Entering a different password here from
the one set in the New Local Enabled field will result in a fail message.
Click the Apply button to accept the changes made.
SSL Settings
Secure Sockets Layer, or SSL, is a security feature that will provide a secure communication path between a host
and client through the use of authentication, digital signatures and encryption. These security functions are
implemented through the use of a cipher suite, which is a security string that determines the exact cryptographic
parameters, specific encryption algorithms and key sizes to be used for an authentication session and consists of
three levels:
1 Key Exchange: The first part of the Cipher suite string specifies the public key algorithm to be used. This
switch utilizes the Rivest Shamir Adleman (RSA) public key algorithm and the Digital Signature Algorithm
(DSA), specified here as the DHE DSS Diffie-Hellman (DHE) public key algorithm. This is the first
authentication process between client and host as they “exchange keys” in looking for a match and
therefore authentication to be accepted to negotiate encryptions on the following level.
2 Encryption: The second part of the cipher suite that includes the encryption used for encrypting the
messages sent between client and host. The Switch supports two types of cryptology algorithms:
Stream Ciphers – There are two types of stream ciphers on the Switch, RC4 with 40-bit keys and RC4 with
128-bit keys . These keys are used to encrypt messages and need to be consistent between client and host
for optimal use.
CBC Block Ciphers – CBC refers to Cipher Block Chaining, which means that a portion of the previously
encrypted block of encrypted text is used in the encryption of the current block. The Switch supports the
3DES EDE encryption code defined by the Data Encryption Standard (DES) to create the encrypted text.
3 Hash Algorithm: This part of the cipher suite allows the user to choose a message digest function which
will determine a Message Authentication Code. This Message Authentication Code will be encrypted with a
sent message to provide integrity and prevent against replay attacks. The Switch supports two hash
algorithms, MD5 (Message Digest 5) and SHA (Secure Hash Algorithm).
These three parameters are uniquely assembled in four choices on the Switch to create a three-layered encryption
code for secure communication between the server and the host. The user may implement any one or combination
of the cipher suites available, yet different cipher suites will affect the security level and the performance of the
secured connection. The information included in the cipher suites is not included with the Switch and requires
downloading from a third source in a file form called a
certificate . This function of the Switch cannot be executed
without the presence and implementation of the certificate file and can be downloaded to the Switch by utilizing a
TFTP server. The Switch supports SSLv3. Other versions of SSL may not be compatible with this Switch and may
cause problems upon authentication and transfer of messages from client to host.
The SSL Settings window located on the next page will allow the user to enable SSL on the Switch and implement
any one or combination of listed cipher suites on the Switch. A cipher suite is a security string that determines the
exact cryptographic parameters, specific encryption algorithms and key sizes to be used for an authentication
session. The Switch possesses four possible cipher suites for the SSL function, which are all enabled by default.
To utilize a particular cipher suite, disable the unwanted cipher suites, leaving the desired one for authentication.
When the SSL function has been enabled, the web will become disabled. To manage the Switch through the web
based management while utilizing the SSL function, the web browser must support SSL encryption and the header
of the URL must begin with https://. (Ex. https://xx.xx.xx.xx) Any other method will result in an error and no access
can be authorized for the web-based management.